The present invention relates to pin movement control mechanisms in injection molding machines and more particularly to electrically powered actuating mechanisms for axial drive of pin mechanisms which are disposed in a melt flow channel in an injection molding apparatus. Hydraulic and pneumatic actuators have traditionally been used to control the movement of a pin used, for example in a valve, in injection mold apparati due to the high pressures under which molten polymer is injected into the mold cavity such pressures typically being in excess of 50 MPa, e.g. around 100 Mpa and in high pressure molding in excess of 200 Mpa. Such conventional actuators are complex in design, maintenance intensive, bulky in size and relatively undesirable in environments of higher cleanliness.